Since its official launch last April at the 2008 Hanover Messe, Eldon’s complete switchgear system, the EPS or Eldon Power System, has garnered positive responses throughout the European market, particularly in Norway, Sweden and Spain where panels builders have been very excited and sales figures have been strong. Eldon, not content to rest on its laurels, is working hard to improve this new, state-of-the-art product. The EPS now comes with a specially-designed roof, engineered to handle any problems caused by arcing due to internal faults.
Busbar before test Arching effects in busbar
When an internal fault occurs, it can cause a release of arc energy that raises the atmospheric pressure within the enclosure. This, in turn, causes internal overpressure and local overheating that results in mechanical and thermal stressing of the low-voltage switchgear. Subsequently, the materials involved may produce hazardous gases or vapors, which may then be discharged to the outside of the enclosure.
Eldon’s specially-designed roof allows the internal overpressure to go out of the enclosure through the top of the switchgear system, thereby preventing thermal stress and ensuring the safety of the operators around the enclosure.
This is important as Eldon’s EPS switchgear system is typically used as the main electric distribution board, when the power usage run from 1000 A to 5000A. Possible applications including, hospitals, schools, university campuses, hotels, public buildings, sport centers, residential buildings, industrial facilities, dairies, warehouses, road and rail bridges, canal lock controls and railroad controls.
In order to guarantee the proper performance of the newly-designed roof during actual arcing, the EPS roof was tested according to the standard IEC 61641: “Enclosed Low-Voltage Switchgear and Controlgear Assemblies—Guide for Testing Under Conditions of Arcing Due to Internal Faults.”
This testing standard makes allowances for the effects of internal overpressure on covers, doors and other switchgear components while also taking into consideration the thermal effects of the arc or its roots on the enclosure and of ejected hot gases and glowing particles, but not damage to internal partitions. The test simulates situations when all doors and covers are closed and correctly secured, but does not cover all effects which may constitute a risk, such as toxic gases.
The testing on the EPS was carried out by ENAC Labein Tecnalia ( Test report CE35-09-BS-02 ). The EPS passed with flying colors, as all criteria indicated in the standard were satisfied.
These included:
- Doors and covers did not open (only slight deformation of the back cover)
- Neither fragmentation of the enclosure nor projection of small parts occurred
- Arcing did not cause holes in the accessible sides of the enclosure
- Indicators did not ignite due to the effect of hot gasses
- Enclosure remained connected to its earthing point
- Arc was not propagated to the adjacent compartments